If you need a Flash file to try this with, here you go. At least on Windows, you can paste the URL directly into the file name field of the "Open local file" on the demo page.
If you haven't seen it, GH has a non-querystring URL that will likely work in places that are not tolerant of either querystrings or special characters in "filenames":
https://github.com/claus/as3swf/blob/master/examples/dumps/A...